In this study, we describe food availability and diet selection of the Red Knot Calidris canutus islandica wintering in three estuarine bays on the French Channel coast. We examined whether the ...distribution of birds is related to the density and availability of high quality prey. Results indicate strong seasonal and inter-annual variation in the abundance of birds and considerable variation in prey-item abundance and diet selection depending upon site. At Mont Saint-Michel Bay, the prey community was dominated by Baltic Tellins, Macoma balthica. As expected from their high meat-to-shell ratio, Macoma contributed more than 90% of the diet. Most of the cockles, Cerastoderma edule were too large and their quality too low to be preyed upon. Less than 100 km away, in Saint-Brieuc Bay, Red Knots mainly selected the Thin Tellin Tellina tenuis. Although Tellina are a lower quality prey than Macoma, they occurred at a high density and in some winters might explain why the number of Red Knots exceeds those at Mont Saint-Michel Bay. At Bay des Veys, Normandy, Red Knots were restricted to a small intertidal area and fed on Abra tenuis, Macoma balthica and Hydrobia ulvae.
Coastal bays provide habitats for juveniles and adults of many marine species. Mont Saint-Michel Bay (MSMB, France) hosts a highly diversified fish community and constitutes one of the most important ...nursery grounds for many commercially exploited marine species, such as sea bass, flatfish, clupeids and rays in the English Channel. Besides, MSMB also suffers from the massive invasion of an exotic mollusc, the American slipper-limpet (
Crepidula fornicata, L.). This species arrived four decades ago and now represents the main filter-feeder biomass in the bay (150 Mt), an order of magnitude larger than local farmed and natural shellfishes. Recent analyses underlined the impact of this small gastropod on the trophic structure of this bay and its negative influence on juvenile sole densities in the nursery grounds. The present study uses a geostatistical approach to explore the effect of the extension of the slipper-limpet on flatfish (common sole
Solea solea, L.; plaice
Pleuronectes platessa, L.; brill
Scophthalmus rhombus, L. and flounder
Platichthys flesus, L.) spatial distribution. Data collected during survey of the MSMB at the end of the 1970s and three decades later have been used to build interpolated maps of (1) slipper-limpet and (2) flatfish spatial distributions. Slipper-limpets were concentrated in a small area, in the western part of the MSMB, in the 1970s while today they occupy half of the bay. This rapid proliferation led to the decrease of available surface for flatfishes, which previously occupied the whole bay and are now restricted to its eastern part. The present study highlighted that the negative influence on fish habitat in MSMB is apparently more related to changes in the substratum than to trophic interactions. This invasion has possible consequences on flatfish population renewal at a large scale and may also damage other benthic or demersal species, such as rays.
► Mont Saint-Michel Bay is a nursery ground for many species, including flatfish. ► The bay is invaded by slipper-limpets whose shells modify the sediment structure. ► Spatial distribution of four flatfish has changed since slipper-limpet invasion.
Die im Jahre 1905 von Gustav Gröber ins Leben gerufene Reihe der Beihefte zur Zeitschrift für romanische Philologie zählt zu den renommiertesten Fachpublikationen der Romanistik. Die Beihefte pflegen ...ein gesamtromanisches Profil, das neben den Nationalsprachen auch die weniger im Fokus stehenden romanischen Sprachen mit einschließt. Zur Begutachtung können eingereicht werden: Monographien und Sammelbände zur Sprachwissenschaft in ihrer ganzen Breite, zur mediävistischen Literaturwissenschaft und zur Editionsphilologie. Mögliche Publikationssprachen sind Französisch, Spanisch, Portugiesisch, Italienisch und Rumänisch sowie Deutsch und Englisch. Sammelbände sollten thematisch und sprachlich in sich möglichst einheitlich gehalten sein.
Diverse species assemblages are often associated with a diversity of habitat structures. Sedimentary systems seem to be no exception, as within sedimentary systems benthic species diversity within a ...sample point appears to correlate with sediment grain size complexity. However, it remains to be shown whether total benthic species diversity relates to a system’s sediment heterogeneity across multiple systems. In the present paper we examined whether bivalve diversity is associated with: (1) sediment heterogeneity across systems and (2) sediment grain size complexity within systems, at 9 temperate and tropical tidal flat systems. Although bivalve life-history strategies, like post-settlement habitat selection, might suggest that sediment heterogeneity should be important for bivalve species, bivalve diversity and sediment heterogeneity were not associated across systems. Interestingly, the association between total benthic diversity and sediment heterogeneity was also not significant, suggesting that changing species composition across systems does not account for the lack of a correlation between bivalve diversity and sediment heterogeneity. Instead of habitat differentiation, bivalve diversity within a sample point was highest in ‘complex’ fine-grained sediments and bivalve distributions showed a large degree of distributional overlap in all systems. The results of this study at both smaller and larger spatial scales suggest that coexistence between bivalve species in diverse tidal flats is not associated with increased sediment heterogeneity.
Si les membres des « Ordres du roi », expression désignant, sous l’Ancien Régime, l’Ordre de Saint Michel créé en 1469 par Louis XI, et l’Ordre du Saint-Esprit créé en 1578 par Henri III, sont connus ...et précisément recensés, l’histoire de l’art, en l’occurrence l’examen des toiles, gravures ou sculptures produits entre les XVe et XVIIIe siècles, et en particulier des portraits peints et gravés de chevaliers, permet de progresser dans la compréhension de la fonction et du fonctionnement de ces deux institutions. L’invention et le recours aux ordres de chevalerie par des puissances étatiques centralisatrices ne peuvent être dissociés du processus qui vit en Europe, du Moyen Âge à nos jours, l’affirmation et l’ascension progressive de l’individu, sinon de l’individualisme, face à la collectivité, aux corporations, aux « castes » d’un « vieux monde » solidement organisé. Loin de servir cette vaste émancipation, comme on le conçoit a priori, les ordres de chevalerie agissent à son encontre en permettant certes aux chevaliers décorés d’assouvir leur désir de distinction, mais uniquement de façon superficielle – en leur offrant la possibilité de ressembler au roi –, sans conséquence sur l’ordonnancement des affaires de l’État. À partir de l’étude du don du cordon bleu aux fils de France, des insignes accaparés et des signes que l’on prend pour des insignes alors qu’ils n’en sont pas et de l’altération, par accident, par intention ou par incompréhension des motifs visuels des Ordres du roi, il s’agit de démontrer comment ces derniers constituent des outils de neutralisation d’ordre esthétique, par le pouvoir, des ambitions aristocratiques.
If the members of the "Orders of the King", which refer, under the Ancien Régime, to the Order of Saint Michael created in 1469 by Louis XI of France, and the Order of the Holy Spirit created in 1578 by Henry III of France, are well known and precisely identified, history of art, through the examination of canvases, engravings or sculptures produced between the 15th and the 18th centuries, and in particular painted and engraved portraits of knights, paves the way to a better understanding of the Orders in terms of roles and operation. The invention and the use of chivalric orders by a centralized state is intimately linked to the process that led in Europe, from the Middle Ages to present days, to the rise of the individual, if not the rise of individualism itself, in a strong society made up of corporations and “castes”. These orders were not founded to strengthen this dynamics of emancipation, as one could think. Even if the knights were given the right to stand out from the crowd, thanks to insignias that give them the illusion to look like the king, it was only in a superficial way, without affecting the affairs of the state. Our thesis, which consists in demonstrating how the “Orders of the King” were used as a tool of aesthetic neutralization, by the King, of aristocratic ambitions, relies on the study of the Sons of France’s Cordons Bleus – the ribbon from which the Cross of the Holy Spirit was hung was blue –, insignias that are not precisely insignias of the Orders of the King, and the modification by accident, intent or misconception of the Orders of the King’s symbols and representations.
The effects of sheep grazing on plant community structure and diversity were studied in saltmarshes of the Mont-Saint-Michel bay. This study took place at two scales: (1) at the scale of the entire ...bay to explore the changes in plant community over a ten year period; and (2) locally with the use of experimental exclosure set up to mimic the abandonment of grazing. Moderate grazing generally enhanced plant richness and diversity, while the absence of grazing and overgrazing lead to a decrease in diversity and richness. The development of management strategies is becoming critical to preserve the diversity of saltmarshes functions.
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